ニトリル酸化物の内分子1,3-二極エネ反応は,段階的な1,1-サイクロアディション/レトロエネメカニズムによって発生する
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Journal of the American Chemical Society
|November 6, 2003
まとめ
密度関数理論は,窒素酸化物とアルケンの間の分子内1,3-二極性エネルギー反応は3段階のプロセスであることを明らかにします. 競争的な反応が支配的になり得る,特に長い鎖や代替品がない場合.
科学分野:
- 有機化学 オーガニック・ケミストリー
- コンピューティング・ケミストリー
背景:
- 分子内1,3-二極エネ反応は,重要な合成変換である.
- ニトリル酸化物は,サイクル添加反応で使用される多用途の1,3-二極体です.
研究 の 目的:
- ニトリル酸化物とアルケンの間の分子内エネのような反応の反応機構を計算的方法を用いて解明する.
- 分子内エネルギー反応と他の反応経路の間の競争に影響を与える要因を特定する.
主な方法:
- 反応経路を研究するために,密度関数理論 (DFT) の計算を用いた.
- 反応中間物質と移行状態の分析が行われました.
主要な成果:
- 反応は,カルベノイド添加とレトロエネ反応を含む3段階のメカニズムを経由して進行します.
- バイサイクルニトロゾ化合物とニトロゾcyclopropane中間物質の形成が特定されました.
- フロキサンへの分子内 (3+2) サイクル添加と分子間ニトリル酸化物の二酸化化は,競合する経路であることが判明しました.
- 反応結果は,テザー長さとトリメチルシリルなどの置換物の存在に敏感です.
結論:
- この研究は,分子内1,3-二極性エネ反応の詳細なメカニズム的な理解を提供します.
- 基板構造を含む反応条件は,望ましい反応への選択性に大きな影響を与えます.
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